Smelting-furnace and the like



J. GAUNT AND D. BROOKFIELD. SMELTING FURNACE AND THE LIKE. APPLICATION man nsc. 26, 19M.

Patented June 29, 1920.

3 SHEETS-SHEET I.

J. GAUNT AND D. BROOKFIELD. SMELTING FURNACE AND THE LIKE.

APPLICATION FILED DEC. 26, l917 Patented J 11116 29, 1920.

3 SHEETS-SHEET 2.

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APPLICATION FILED 05c. 26, 1917.

1,844,87 8. Patented June 29, 1920,

3 SHEETSSHEET 3.

IUNITEDSTATES PATENT OFFICE.

JAMES eAuN'r AND DOUGLAS BROOKFIELD, or LONDON, ENGLAND.

. .s MELllNGFURNAcE AND THE LIKE.

Specification of Letterslatent. Patented J 29 1 20 Application med December 26,1917. Serial No. 208,886.

To all who-writ may concern 7 Be it knownthat we, JAMEs GAUNT and DOUGLAS ,BROOKFIEL-D, subjects of the King of Great Britain, residing at London, England, have invented new and useful Improvements in SmeltingFurnaces and the like, of which the following is a specification.

This invention relatesto improvements in furnaces such as are commonly used for smelting and refining metals, and the objects of our improvements are to utilize the heat or products of combustion of the .fuel employed to a greater extent than heretofore so as to obtain an increased efficiency and, when a solid fuel is employed for the purpose, to provide a simple means, or removable ash-pit whereby the ashes can be extracted within the shortest space of time, and to generally improve the construction and design with a View to increasing efficiency and to facilitate handling and manipulation of the various parts in the case ofrenewals or repairs.

The introduction of preheated airblast into; such furnaces isalready practised, and generally the exhaustgases fromthefurnace have been employed for this purpose, the

blast being conveyed in a spiral conduit disposed around the uptake.

The examples of the embodiment of our improvements hereinafter described are'to that class of furnace in ,Whichcoke is used as the fuel for the purpose, but it will be obvious that any other class of fuel may be employed, and that the improvements are equally applicable towhat are known as the pit or tilting furnaces.

Inorder that our invention may be clearly understood, we will now describe the same with theaidof the accompanying-five sheets of drawings, in which Figure 1 is a sectional elevation and Fig. 2 a half plan and sectional plan'taken online X.X of Fig. 1 of a furnace with our improvements applied thereto. Fig. 3 is a sectionalelevationof a modification of a similar furnace .With the refractory lining removed therefrom. Fig. la sectional plan taken on line YY of Fig. 3. Fig. 5 a transverse section with the refractory lining in situ, and Fig. 6 a sectional plan on line Z.Z of Fig. 5.

Referring now to Figs. 1 and 2, the smelting furnace consists essentially of a bodya of cast iron or other suitable material, to Which is hingeably attached a base or ashpit b and a preheater c for the metal contamed 1n the hopperd that forms a cover or closure 6 for the furnace and serves for the escape of the waste products of combustion. The combined cover 6 and metal container (Z 1s sultably attached to the outer body or casting a of the furnace so that it can be readily raised from its seating f and swung out of the way to expose the whole of the interior of the furnace to View.

The body or casing a of the furnace, which may be of circular or other shape, is preferably made in halves and exterior lugs or flanges 9 provided to bolt thevtwo sections together. The upper edge is provided with suitable flanges 7a which serve on the one hand as a closure for the air conduits hereafter described, and on, the other hand for supporting the cover 6 and metal container (Z as aforesaid. I I

At'the base of the body. or casing a is provided an internal flange j with depending lugs 70 that support a'circular grate m, the central portion of which is provided with a suitable surface n for carrying a block 0 of refractory material 011 which the crucible p rests. This internal flange j serves for sup porting not only the grate but the interior refractory lining Q ofthe furnace.

The interior of the body or casing a is provided with radially disposed ribs 1" extending more or less from top to bottom of the said casing. These ribs combined with the steel or other plate cylinder 8 (which cylinder 8 constitutes the interior wall or shell to receive the refractory lining g ofthe furnace) form conduits t for conveying the air-blast to beneath the grate 072. As will be seen the airblast is delivered from the fan or blower on both sides of the furnace by the pipes a into the opposite conduits 25 passing downward toward thebase and due to the ribs 7* not extending to the bottom is free to pass into the next conduit on either side in an upward direction, thence into the next conduit at the top over the ribs 1", then downward, thus making a zig-zag course before it is discharged through the orifices o into the space beneath the grate.

Any convenient number of inlet connections to may be provided on the exterior of the body a for coupling up the conduits t to the fan or blower employed for the blast, and likewise the internal flange on the body a maybe provided. with holes 1) suitably disposed to establish communication with the space beneath the grate mso that the discharge may be distributed evenly around the entire surface of the said grate.

The grate m is supported on depending lugs 75 from the internal flange j, and is provided with suitable projections or lugs m which correspond with the said depending lugs 70, whereby the grate m can be readily removed by simply turning the lugs it out of engagement with the lugs Z: for the purpose of repair or renewal.

To the base of the casing or body a of the furnace is hingedly attached the hollow cover I) that serves for the distribution of the air or blast admitted to beneath the grate m, the section of which is preferably of a centrally indented dome, as seen in Fig. 1, the outer curve in conjunction with the center cone serving to convey the blast admitted directly toward the air spaces provided in the grate m. This cover Z) also serves as an ash-pit, and due to being hin ed to the body, as hown at y, can be readily lowered and the ashes removed therefrom in so short a time as to practically not interfere with the working of'the furnace. The cover Z) may be balanced, as for example by the weight 2, to facilitate the manipulation of the same, and a suitable latch fastening 8 may be employed to retain the same in its closed position.

The combined cover a and metal container (Z that forms the closure for the top of the furnace may be made of cast iron or other suitable material with an upwardly extending portion 1 provided with the ordinary lining 5 of refractory material, the upward extension i of this cover 6 being in the form of a hopper or container (Z is disposed ina plane directly above the crucible 29 which rests on the central portion 0 of the grate m as before described. At the base of this hopper (Z we prefer to provide an internal extension 6 which more or less depends toward the top of the crucible and forms together with the interior lining of the cover a deflecting surface whereby the products of combustion are conveyed more or less across the furnace, and the hottest vapors or gases are thus conveyed on to or toward the surface of the refractory lining that forms the hopper or metal container (Z instead of the products, as in the ordinary course, being conveyed through the central portion of the charge situated in the hopper.

In order to facilitate the manipulation of the cover 0, trunnions 7 are provided on the upper part 1 with which engage the ends 8 of the forked lever 9 that is pivotally mounted on the bracket 10 which is free to rotate on the vertically disposed spindle 11 secured in any convenient manner to the body a. The forked lever 9 is preferably provided with a socketed end 12 into which the removable lever 13 is placed for raising the cover 6 from contact with the upper flanges h of the body or casing a of the furnace, when the same may be swung on the spindle 11 out of the way by the manipulation of the lever 13.

It will now be understood that the preheating of the air-blast preparatory to its introduction into the furnace is effected by conduction through its intimate contact with the wall or lining s of the furnace, and that in the event of a temporary breakdown of the fan orblower whereby the blast would be interrupted, the admission of air to support combustion may :be efiected by the removal or lowering out of the bottom cover or ash-pit b to allow the ordinary admission of air at atmospheric pressure to support combustion of the furnace charge until such time as the blast is restored.

Referring now to the modification and details illustrated in Figs. 3-6, it will be observed that the inlet pipe u from the fan 14c is connected up to a common inlet w that communicates with the conduits t situated around the furnace, and as will be seen the air is conveyed in a downward direction in the conduit t where it divides at the bottom and rises in the conduits t whence it passes over the top of the adjacent ribs '1- into the conduits t travels in a downward direction and is discharged through the orifices o to beneath the grate, as indicated by the arrows in Fig. 3.

The method illustrated for raising the cover 6 is a modification whereby the lever 13 (Figs. 1 and 2) may be dispensed with, and in place thereof the forked lever 9 is provided with an extension 15 which is actuated by the hand-wheel 16 operating the screw 17 which is in engagement with a suitably fixed nut in the bracket 18 fixed to the standard 10 which is rotatably mounted on the vertical spindle 11 secured to the body or casing a in any convenient manner. The preheater c'is in this case provided with a separate lid or cover 19 which is hinged at 20 to the casing 4, and is provided with a depending internal deflecting surface 21 for the purpose of arresting the flow of the products of combustion through the charge situated in the hopper 03.

Referring particularly to Figs. 5 and 6, a convenient method is shown of securing the segmental refractory blocks within the cover 6 of the furnace which consists in providing semicircular holes at the radiating edges or joints of the refractory blocks 22 for the reception of the bolts 23, the heads of which snugly fit the recesses 24 while the screwed portions or stems of the bolts pass through holes 25 formed in the cover 6. A similar method may be also adopted for securing the block 0 onto the central portion a of the grate m.

Claims.

1. A cylindrical casing open at its upper and lower ends and provided on the inner side of its wall with vertical, radially disposed spaced ribs; a cover on upper end of the casing, a hopper mounted on the cover; a grate, grate-supporting means with which the lower end of the casing is provided; a refractory lining in said casing supported also 011 said grate-supporting means, and coacting with said spaced ribs to form a circuitous air conduit around the lining and to a point below the grate; an air blast pipe connected to the casing, a crucible mounted on the center of the grate, and a detachable closure for the lower end of the casing, said closure being hollowed in its upper side and hence forming a chamber to conduct the air blast from said conduit to the air spaces in the grate.

2. A smelting furnace comprising a casing, a cover forming a closure therefor, and a cylinder disposed within said casing and receiving the refractory lining of the furnace, the interior of said casing being provided with a plurality of radially disposed ribs so arranged that said ribs and said cylinder together constitute conduits for conveying the air blast in a circuitous path to beneath the grate of the furnace.

8. A smelting furnace comprising a casing, cover forming a closure therefor, a cylinder disposed within said casing and receiving the refractory lining ofthe furnace, the interior of said casing being provided with a plurality of radially disposed ribs so arranged that said ribs and said cylinder together constitute conduits for conveying the air blast in a circuitous path to beneath the grate of the furnace, and means for distributing the air blast so admitted comprising a hollow cover of such section that the blast is thereby admitted directly toward the air spaces in said grate.

4. A smelting furnace comprisin a casing, a cover forming a closure therefor, said cover being provided with an upward extension forming a hopper, said hopper having a depending internal extension and a cylinder disposed within said casing and re ceiving the refractory lining of the furnace, the interior of said casing being provided with a plurality of radially disposed ribs so arranged that said ribs and said cylinder together constitute conduits for conveying the air blast in a circuitous path to beneath the grate of the furnace.

In testimony whereof we have signed our names to this specification.

JAMES GAUNT. DOUGLAS BROOKFIELD. 

